Buggy code:
public class Combo extends Composite { boolean noSelection ; boolean ignoreModify ; boolean ignoreCharacter ; int visibleCount = 5 ; public static final int LIMIT ; static final int CBID_LIST = 1000 ; static final int CBID_EDIT = 1001 ; static int EditProc ; static int ListProc ; static final int ComboProc ; static final TCHAR ComboClass = new TCHAR ( 0 , "COMBOBOX" , true ) ; public Combo ( Composite parent , int style ) { } public void add ( String string ) { } public void add ( String string , int index ) { } public void addModifyListener ( ModifyListener listener ) { } public void addSelectionListener ( SelectionListener listener ) { } public void addVerifyListener ( VerifyListener listener ) { } int callWindowProc ( int hwnd , int msg , int wParam , int lParam ) { } boolean checkHandle ( int hwnd ) { } protected void checkSubclass ( ) { } static int checkStyle ( int style ) { } public void clearSelection ( ) { } public Point computeSize ( int wHint , int hHint , boolean changed ) { } public void copy ( ) { } void createHandle ( ) { } public void cut ( ) { } int defaultBackground ( ) { } void deregister ( ) { } public void deselect ( int index ) { } public void deselectAll ( ) { } public String getItem ( int index ) { } public int getItemCount ( ) { } public int getItemHeight ( ) { } public String [ ] getItems ( ) { } String getNameText ( ) { } public int getOrientation ( ) { } public Point getSelection ( ) { } public int getSelectionIndex ( ) { } String getSelectionText ( ) { } public String getText ( ) { } public int getTextHeight ( ) { } public int getTextLimit ( ) { } public int getVisibleItemCount ( ) { } boolean hasFocus ( ) { } public int indexOf ( String string ) { } public int indexOf ( String string , int start ) { } int mbcsToWcsPos ( int mbcsPos ) { } public void paste ( ) { } void register ( ) { } public void remove ( int index ) { } public void remove ( int start , int end ) { } public void remove ( String string ) { } public void removeAll ( ) { } public void removeModifyListener ( ModifyListener listener ) { } public void removeSelectionListener ( SelectionListener listener ) { } public void removeVerifyListener ( VerifyListener listener ) { } boolean sendKeyEvent ( int type , int msg , int wParam , int lParam , Event event ) { } public void select ( int index ) { } void setBackgroundPixel ( int pixel ) { } void setBounds ( int x , int y , int width , int height , int flags ) { } void setForegroundPixel ( int pixel ) { } public void setItem ( int index , String string ) { } public void setItems ( String [ ] items ) { } public void setOrientation ( int orientation ) { } public void setSelection ( Point selection ) { } public void setText ( String string ) { } public void setTextLimit ( int limit ) { } public void setVisibleItemCount ( int count ) { } void subclass ( ) { } boolean translateTraversal ( MSG msg ) { } boolean traverseEscape ( ) { } void unsubclass ( ) { } String verifyText ( String string , int start , int end , Event keyEvent ) { } int wcsToMbcsPos ( int wcsPos ) { } int widgetExtStyle ( ) { } int widgetStyle ( ) { } TCHAR windowClass ( ) { } int windowProc ( ) { } int windowProc ( int hwnd , int msg , int wParam , int lParam ) { } LRESULT WM_CTLCOLOR ( int wParam , int lParam ) { } LRESULT WM_GETDLGCODE ( int wParam , int lParam ) { } LRESULT WM_KILLFOCUS ( int wParam , int lParam ) { } LRESULT WM_SETFOCUS ( int wParam , int lParam ) { } LRESULT WM_SIZE ( int wParam , int lParam ) { } LRESULT wmChar ( int hwnd , int wParam , int lParam ) { if ( ignoreCharacter ) return null ; LRESULT result = super . wmChar ( hwnd , wParam , lParam ) ; if ( result != null ) return result ; switch ( wParam ) { case SWT . TAB : return LRESULT . ZERO ; case SWT . CR : postEvent ( DefaultSelection ) ; case SWT . ESC : <START_BUG> if ( ( OS . SendMessage ( hwnd , CB_GETDROPPEDSTATE , 0 , 0 ) ) == 0 ) { <END_BUG> return LRESULT . ZERO ; } } return result ; } LRESULT wmClipboard ( int hwndText , int msg , int wParam , int lParam ) { } LRESULT wmCommandChild ( int wParam , int lParam ) { } LRESULT wmIMEChar ( int hwnd , int wParam , int lParam ) { } }

Fix:
if ( ( OS . SendMessage ( handle , CB_GETDROPPEDSTATE , 0 , 0 ) ) == 0 ) {